Treatment of the Child With Severe Limb Deficiencies

Götz Gerd Kuhn, M.D.


First of all, we should always think about how we can help the child without the use of technical devices, or with a minimum of them.

Clubhand

Among upper-limb malformations, clubhand is the most common. We treat it as early as possible with a corrective three-point night-splint. This splint has a screw for day-to-day adjustment so that we may push the growing bone in the direction we wish it to go (Fig. 1 ). In cases of drophand or club-drophand we try to increase function with a spring-loaded, three-point day-splint (Fig. 2). The force of the spring should be as low as possible, thus enabling the child to volarflex the hand against the force exerted. To assist in lifting an arm with limited strength or function we also give spring-loaded support with an inclined joint located under the axilla. When the arm is moved toward the middle of the chest, it is automatically lifted (Fig. 3 ). The arm can be lowered against the spring support.

Partial Hands

For partial hands without gripping function and with severely underdeveloped fingers, we provide forearm clips bearing adjustable counterplates or individually shaped holders for writing or eating utensils (Fig. 4 , Fig. 5 , and Fig. 6 ).

Below-Elbow Fittings

If the child has a long below-elbow stump, we fit it with an open-end socket (Fig. 7 ). This construction enables the patient to use the sensory surface of his stump as well as the terminal device. The socket is provided with a friction joint on the dorsum of the prosthesis so that the terminal device can be bent away from the end of the stump. To increase the range of motion in very short or "frozen" stumps, we place this joint on the radial side of the prosthesis. It allows preflexion of the arm in any useful position.

Below-Elbow Harnesses

The harness for the below-elbow prosthesis is almost always of the same type (a figure-9 type) without fixation on the upper arm. The harness strap is made of two layers of webbing with the control cable running between them (Fig. 8 ). In very short forearm cases the strap is attached to the socket more distally so that it acts as a flexion support (forearm lift). If the stump is too short for any lifting, the forearm muscles may be used for myoelectric control of the hand. Also, very badly burned above-elbow stumps have been used successfully for myoelectric control (Fig. 9). By this method we are able to provide an active above-elbow prosthesis without any harness as we have done for years with cosmetic above-elbow arms. For most body-powered prostheses a "chestfree" triple-control harness is used. The term "chestfree" implies that there is no harness strap running across the chest. The shoulder-disarticulation prosthesis is supplied with a triple-control harness and a cheststrap as well as a shoulder joint giving abduction controlled by friction or locking. A shoulder-girdle amputation (forequarter) we normally fit with passively locked elbow- and shoulder-abduction and flexion units. The harness supplies two controls; one for forearm flexion and the other for the terminal device (Fig. 10 ).

Modular Prostheses

Parts for skeletal or modular-arm prostheses are commercially available and this technique of fitting is widely used. The cover is individually shaped on prefabricated urethane-foam blocks and finished with skin-colored stockinette (Fig. 11 and Fig. 12 ).

Phocomelias and Amelias

For the phocomelic shoulder-disarticulation prosthesis we use a so-called "stola" instead of a socket because it does not require a strap across the chest (Fig. 13 ). The double "stola" has a joint or flexible part at the neck junction. We normally fit double amelics or phocomelics with hybrid prostheses; that is, on one side a body-powered, skeletal-type prosthesis, and on the other side a pneumatic prosthesis, using conventional techniques, since at present there are no skeletal parts available for pneumatic prostheses (Fig. 14A and Fig. 14B ). For the body-powered prosthesis we gain additional force by using a metal-reinforced belt (Fig. 15 ). Shoulder movement (scapular elevation) against this belt gives good power. To increase function and comfort we developed a triple-control harness with voluntary lengthening and shortening of all three control cables. It is a body-powered harness but the length is controlled by the use of pneumatic muscles (Fig. 16 ). One other interesting fitting we were able to obtain was the fixation of a shoulder-disarticulation prosthesis without the use of a strap on the chest or the neck.

Writing Aids

In order to facilitate writing for the phocomelic child, we have developed different writing aids such as: simple pencil extensions, adaptive devices to hold two or three pencils (Fig. 17 ), or writing aids with spring-loaded axilla supports and with clasps adaptable to every thickness of crayon, pencil, or fountain pen. Still other writing aids have been made with a stabilizing shell for the hand to transmit the writing motions (Fig. 18 ).

Eating

We have made several different eating aids: spoons with little rings for better fixation of unstable fingers (Fig. 19 and Fig. 20 ), swivel spoons for use in a prosthesis, and even a spoon with free movement in two dimensions (Fig. 21 ). We achieved the necessary stability by moving (displacing) the point of balance during the different steps of eating. Another aid is the disk wedge (Fig. 22). This device makes it easier to fill the spoon or fork by inclining the dish or plate when it is turned. For toileting we have constructed two aids: a friction board, fixed to the wall, which helps the armless patient take off or put on his clothes (Fig. 23 ), and a device which, although not perfected yet, enables the child to wipe himself after defecation (Fig. 24 ).

Lower-Extremity Malformations

Children with malformations of the lower extremities we put in pelvic baskets on stubbies, first without-later with-traction or extension-straps on the feet. To allow movements of the extremities, we make the basket in two parts and connect them with an elastic strap. We also tried to arrange for the patient to walk in a sitting position but were not successful (Fig. 25 ). A further development is a formstable belt, which controls lordosis in the standing position and to which ball-and-socket joints with limited motion are attached (Fig. 26 ). All of these prostheses have been made using a skeletal or simplified modular technique with urethane-foam covering so that it is easy to lengthen the leg, change the socket or knee mechanism, or modify the alignment.

Sometimes we have fixed a stabilizing lever arm or outrigger which is attached above the prosthetic feet and touches the ground beside the shoes (Fig. 27 ). These devices are typically used only for the first few days. The feet of the child are attached by simple extensions to an adjustable footrest (Fig. 28 ). We have also made linked baseplates to provide an automatic correction of the foot when it is weight-bearing. We respect and protect the joints of the malformed extremities as much as possible and utilize them for active movement of the limb. To protect the head of the child with four malformed limbs, we provide a soft helmet (FIg. 29 ) or, in some cases, an individually constructed metal helmet. To enable such a child to use his malformed foot instead of the missing hand we have constructed an orthosis which permits him to slip the foot in and out very easily and quickly (Fig. 30 ).

Kondylen Bein Münster (KBM) Prosthesis

For children with lower-extremity amputations we have also used the KBM prosthesis successfully, i.e., a below-knee prosthesis which does not cover the patella but has supracondylar fitting and suspension. In the United States this limb is called the supracondylar tibialis prosthesis (STP) or wedge-suspension below-knee prosthesis. It seems that the osteomyoplastic amputation prevents the overgrowth of the bone (Fig. 31 ). We have developed all the necessary parts, adapters, and joints to make skeletal prostheses for children as well as for adults. This system can be used both for immediate fitting and for the definitive prosthesis with special devices, as well as with many of the conventional feet and knees. Alignment devices for temporary or permanent installation are also available. In order to give the conventional prosthesis a foam cover, we created the "wood-skeleton" technique which is useful in many cases when the regular skeletal procedure is not indicated. The cover is composed of one piece, even in the hip-disarticulation case (Fig. 32 ).

Special Wheelchairs

Some severely handicapped children need special wheelchairs in addition to braces and prostheses (Fig. 33 ). In this area we have constructed several wheelchairs which enable the child to choose between standing, sitting, or horizontal (lying) positions, as well as to lower and to raise his whole body in all these positions (Figs. 34A and 34B , and Fig. 34C ). We also assisted in the construction of a stair-climbing wheelchair which is in production. So far it does not have a battery-powered motor but must be plugged into a wall socket. Some simple cars for use by children with malformed legs and arms have been constructed in our workshop. We also realised the need for special chair seats and for wheelchairs to improve comfort and to prevent or treat scoliosis (Fig. 35 ). In order to get more space in the electric wheelchair and a lower center of gravity, we made a gear-clutch unit with a French wireless disk motor situated in the hub of the wheel (Fig. 36 ). In addition we have created different electronic control systems such as an electronic distance detector which also can be used in an arm prosthesis in place of myoelectric controls. This system has many advantages including simplicity and the provision of easy and secure proportional control. Besides this, we have investigated a voice control for possible applications with wheelchairs, artificial arms (fixed on the wheelchair), or typewriters. For this type of control, sound was used initially. Now any mechanical, electrical, or pneumatic signal may be used. For writing, the signal is transmitted directly, using the international Morse-code system. We have also developed a half-automatic servo-clutch for gasoline-driven cars.

Many of these items now under development may be useful for the handicapped when they become available.

Münster, Germany